What this tool does
If you’re self-employed and buy health insurance through the ACA Marketplace, one number quietly controls thousands of dollars of your health costs: 400% of the federal poverty level. In 2026, earning a dollar over it can wipe out your premium tax credit entirely — the “subsidy cliff.”
This tool shows you, from your own numbers, where you stand relative to that cliff — and how large a deduction would put your modeled MAGI under the threshold. Enter your self-employment income, household size and a few details, and the tool computes your MAGI, the deductions that lower it, and how much each changes the estimated credit. Your income isn't final until the year is — a strong final quarter or a late invoice can carry you over the cliff — so the tool recalculates as your numbers change, while the year is still open rather than at filing.
The tool is built for the person the cliff hits hardest: the freelancer, consultant, or small-business owner.
How the cliff works
The Marketplace premium tax credit is calculated on a sliding scale based on your household income relative to the federal poverty level (FPL). For the 2026 plan year, under current law, the subsidy is available up to 400% of FPL and disappears above it — a hard cutoff rather than a gradual phase-out. The exact threshold depends on your household size and where you live; you can confirm the current figures at healthcare.gov and in the federal poverty guidelines.
Because the subsidy stops rather than tapers, two households a few hundred dollars apart in income can face very different health costs — one receiving thousands in assistance, the other nothing. That discontinuity is what makes the threshold a cliff, and it's why a strong final quarter or a year-end invoice can cost far more than the income it added.
What actually lowers your MAGI
Your subsidy is based on your modified adjusted gross income (MAGI), not your gross revenue — and that distinction decides which deductions matter. Only deductions taken “above the line” reduce MAGI. Pre-tax retirement contributions (a Solo 401(k), SEP-IRA, or for higher earners a cash-balance plan), HSA contributions, and the self-employed health insurance deduction all qualify. Itemized deductions — mortgage interest, state and local taxes, most charitable giving — reduce your taxable income but not your MAGI, so they do nothing for the ACA cliff. Confusing the two is a common and expensive mistake.
The tool weighs the MAGI-reducing options available in your situation, accounts for those you already use, and calculates the additional amount that would put your modeled MAGI under the threshold. Near the cliff, a contribution you were likely making anyway can do two things at once — fund your retirement account and change the estimated credit. Whether a particular contribution is available to you depends on your plan, your earned income and the annual limits; confirm your eligibility with a qualified professional.
How it works, step by step
- 1Enter your situation — self-employment income, household size, age, and your benchmark premium (or let the tool estimate it).
- 2See your position — where your MAGI lands relative to your 400% FPL cliff, and how much subsidy is at stake.
- 3See what moves your position — the MAGI-reducing options open to you, and how much each changes the estimated credit.
- 4Adjust and explore — change a contribution or your income and watch your position and subsidy update.
- 5Track your position through the year — your income isn't final until the year is, so come back as it changes to see where you stand and which scenarios remain available.
The calculation handles an interaction most estimates miss: your health-insurance premiums are themselves deductible, so deducting them lowers your MAGI, which raises your subsidy — which in turn limits how much of the premium you're allowed to deduct. That loop is genuinely circular, and the IRS publishes a specific method for resolving it. A mistake in either direction moves the answer by thousands, and near a cliff the difference between clearing it and missing by a few hundred dollars is the difference between a full subsidy and none.
Two things worth knowing about scope: the tool assumes you claim the subsidy at filing rather than as advance monthly payments, and it estimates your benchmark premium from your age unless you enter your own. Both are adjustable, and both are stated where they apply.
Who it's for (and who it isn't)
The tool is most valuable when you’re near the cliff — close enough that a realistic contribution can bring your MAGI under the threshold. If you’re far over the threshold, no contribution can bridge the gap. If you’re comfortably under, you already qualify — but the tool still shows how much room you have and watches it through the year, so a strong season doesn’t quietly push you over the edge before you notice.